Best chemistry startup sequence after winter season

[tors10]

Hello Folks,

i've read all of the Pool School articles, especially:

Opening your pool- An easy to follow guide

Opening your pool can be stressful. This Pool Start Up guide teaches everything from start-up chemicals, covers, and more for your start up.

www.troublefreepool.com

but it does not give you any insights about the best sequence (e.g. increasing TA also increases PH etc).

Setup:
Location: south of Germany
Fiberglass Pool, 30 cubic meters of water, sand filter, automatic dosing of liquid chlorine and acid (for lowering PH).
Starting up with fresh tap water (PH 8.1, Alkalinity 5, Calcium 50, CYA 0, Chlorine 0).

TFP recomended levels are PH 7.7, Alkalinity 70, Calcium 450, CYA 45, Chlorine 6-7.

But how to get there? What is the best sequence?

Thanks in advance,
Torsten

 

[ajw22]

How are you testing?

pH of 8.1 and TA of 5 make no sense.

Where did you get those TFP recommendations from? TFP does not recommend a CYA of 45. Fiberglass pools do not need calcium unless you have a gas heater.

TFP recommends ranges not specific values. Anywhere in a range is fine.

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

Calcium Hardness - Further Reading

www.troublefreepool.com

 

[tors10]

sorry, TA was wrong. TA is 64 ppm. These values are from the official testing authority:
https://vg-maikammer.de/wp-content/uploads/2024/02/Trinkwasseranalyse-2023.pdf in the second column, "Carbonathärte" in dH (1 dH is 17,9 ppm or mg/l).

I have chosen the mean value of the ideal ranges... PH 7.7, Alkalinity 70, Calcium 450, CYA 45, Chlorine 6-7.
I do see Calcium recommendation here for Fiberglass pools...

 

[ajw22]

You need to adapt TFP Methods to your testing methods which may be different then what TFP recommended levels are based on. And you need to adjust your target values to your pool equipment and environment.

Choosing the mean of the recommendation chart is not the way to do it.

Do you know if the reported TA is the raw TA tested value or an adjusted TA as many pool store tests do? TA recommendations are based on the raw TA values and an adjusted TA makes the TA look lower. Read TA - Further Reading

Some Pool Tests test total hardness and call it Calcium Hardness. Are you sure your test is only reporting calcium hardness.

It is important to understand what to us is a non-standard test is accurately reporting before you try to apply TFP Guidelines which are specifically based on testing with Taylor test kits.

The chart you posted is a generic chart that has the most conservative values to apply globally regardless of pool equipment. If you do not have a gas heater then a modern fiberglass pool does not need calcium unless the manufacturer recommends it.

 

[mmcwhorter]

You sound like a pretty smart guy: buy the TFT-100 test kit and follow the method for a trouble-free pool.

 

[ajw22]

You sound like a pretty smart guy: buy the TFT-100 test kit and follow the method for a trouble-free pool.

Note he is in Germany and so getting one of the TFP recommended test kits is not easy in the EU.

 

[tors10]

I'm using this photometer ( easy to get for me because created by a german company ;-) )

PoolLab.org - official website | Water-i.d. GmbH

The PoolLab® 2.0 Photometer is the perfect solution for professional water analysis of pools and spas.

poollab.org

Pool Water Tester 27 Parameters - Easy to Use Home Pool & Hot Tubs Tester - PoolWaterLAB

Discover the ultimate pool water quality tester with advanced photometer technology. Ideal for hot tubs and pools, ensuring accurate water analysis.

www.poolwaterlab.us

The TA test is done with these tablets:

Reagents for Pool LAB - PoolWaterLAB - Water Tester - Alkalinity-M for Testing Alkalinity 50 Tablets

Measure pool water alkalinity accurately with Alkalinity-M Tablets. Key for maintaining pH balance and water quality.

www.poolwaterlab.us

Hexanedioic acid: https://msds.water-id.com/storage/msds/Alkalinity-M Photometer - TBSPTA - US - en.PDF

I think Calcium test is done with these liquids:

liquid reagents for Pool Lab - PoolWaterLAB - Water Tester - Kit to Measure Calcium Hardness - 50 Tests

Test calcium hardness in pools with this liquid kit. Crucial for water quality and maintaining pool balance.

www.poolwaterlab.us

Acetic acid: https://msds.water-id.com/storage/m...- POL20CH1_from_exp._d._09.2024 - GB - en.pdf
Ethanedioic acid: https://msds.water-id.com/storage/msds/Calcium Hardness No.2 - POL20CH2 - GB - en.pdf

 

[tors10]

Environment:
Fiberglass pool, construction date 2001
Heating: Air-Water Heat Pump
Filtering: Sandfilter
automatic dosing of liquid chlorine and muriatic acid (for lowering PH).

 

[ajw22]

The limits on the range of chlorine testing with the Poollab is an issue with using it with TFP methods…

Poollab 1.0

I know this forum is not generally on-board with electronic water testing devices, but I recently saw a tester called PooLab 1.0 that looked pretty interesting. My friend who works in pool maintenance recently picked one up and absolutely loves it. I was curious if anyone on this forum...

www.troublefreepool.com

 

[ajw22]

Environment:
Fiberglass pool, construction date 2001
Heating: Air-Water Heat Pump
Filtering: Sandfilter
automatic dosing of liquid chlorine and muriatic acid (for lowering PH).

You need to determine what the manufacturer of your 23 year old pool requires for calcium. That is the only reason to maintain a specific level with your equipment list.

Please put your equipment list on your signature.

Create Your Signature - Further Reading

www.troublefreepool.com

 

[tors10]

sorry for the typo, construction date is 2021.

OK, understood the limits of FC testing with Poollab, I will try to get a FAS/DPD Test somewhere.

But, back to my original question:
Where should I start now to examine the best values for my environment?
e.g. start with Alkalinity, raise to 90, look at PH, see if it is stable or not...

 

[ajw22]

Forget about your alkalinity right now.

Get your CYA around 40 and keep your FC in range for your CYA.
FC/CYA Levels

Keep your pH in the 7’s.

Calcium does not matter for you.

Use PoolMath to calculate your CSI and keep it negative to prevent any scaling.

Done!

 

[mgtfp]

sorry, TA was wrong. TA is 64 ppm. These values are from the official testing authority:

Carbonathärte is calcium hardness (CH), as opposed to Gesamthärte further up the list which is Total Hardness (also includes Magnesium Hardness).

Alkalinity doesn't seem to be in the list.

But, back to my original question:
Where should I start now to examine the best values for my environment?
e.g. start with Alkalinity, raise to 90, look at PH, see if it is stable or not...

Keep in mind that higher TA doesn't mean more stable pH. Yes TA is z measure for the buffering capability of the water. But the main contributor to TA is Carbonate Alkalinity (Alkalinity Increaser is Bicarbonate of Soda). The higher the TA, the more oversaturated the water is with dissolved Carbon Dioxide. This wants to gas out, like in an opened soda water bottle, raising pH in the process.

The higher TA is, the faster pH rises. This is only desirable when using Trichlor for chlorination which is acidic, driving pH and TA down. When using liquid chlorine or an SWG (as we recommend to avoid CYA accumulation), which is pH-neutral over the complete chlorination cycle), then there is nothing to counteract the constant pH-rise from CO2 outgassing. In this case a TA around 60-70 usually works better.

Low CSI is not a concern for a FG pool, unless you have a waterline tile with mortar, I would maintain TA just above 50, something like 60 or 70.

pH should then stabilise (or at least rise only slowly) in the higher sevens range. Which is fine if CYA is used, which flattens the pH-dependency of the HOCl concentration (which is the relevant sanitizing chlorine species).

As said above, first concern is CYA/FC.